The US got
involved in the war in Vietnam because it feared that a communist government
would come to power in Vietnam after the National Liberation Front formed a
coalition with the Ho Chi Minh government in the north, against Ngo Dinh Diem's
regime. US policy-planners feared a spread of communism to other countries in
the area.
This involvement in the Vietnam war affected life within the US itself because
of widespread public dissent. Only university graduates were exempt from
compulsory service in the army and this caused even more anger amongst the
minorities and working-class families.